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The progress Iranian specialists have made in the field of
civilian nuclear program has been acclaimed by scientists.
Most important, the pictures give the first public glimpse
of the new centrifuge, known as the IR-2, for Iranian
second generation, International Herald Tribune said
on Tuesday.
There were no captions with the photos, so analysts around
the globe are scrutinizing the visual evidence to size up the
new machine, its efficiency and its readiness for the tough
job of uranium enrichment. They see the photos as an
intelligence boon.
"This is intel to die for," said Andreas Persbo, an analyst in
London at the Verification Research, Training and Information
Center, a private group that promotes arms control. His
comment came on the blog site Arms Control Wonk.
"I don't see anything to suggest this is propaganda," said
Houston Wood 3rd, a centrifuge expert at the University of Virginia.
"They seem to be working on an advanced machine."
Such judgments rest not only on the photographic clues but
also on the Iranian record of successful, if limited, enrichment
and the reports of international inspectors, who have tracked
Iran's bid to develop the new centrifuges.
Engineers use centrifuges for many applications, not just for
enriching uranium. In general, the devices spin fast to separate
all kinds of objects of differing mass and density - for instance,
milk from cream or impurities from wine. To that end, centrifuges
exploit simple laws of physics, doing so in ways that echo common
experience.
A car that veers around a corner throws its passengers to one
side. So, too, a centrifuge throws its contents off what would
normally be a forward course. But it does so relentlessly.
Why do the contents separate? As Newton explained in
his second law of motion, the more massive the object, the
greater the tug.
In the lurching car, an adult feels the force more than a child.
In the centrifuge, heavy objects feel it more than light ones and,
if possible, they move more vigorously toward the outer wall.
Nuclear centrifuges apply the same principle to uranium mined
from the earth's inner recesses, spinning it into constituent parts.
Iran is separating U-235 from U-238. Rare in nature, U-235
easily splits in two to produce bursts of atomic energy. It also
has three fewer neutrons than its cousin, making it slightly lighter
and thus a candidate for centrifuge separation.
First, engineers turn the natural mix of uranium (0.7 and 99.3
percent, respectively) into a gas. Then, the centrifuge throws
the heavier U- 238 atoms toward the wall, letting the rare
U-235 ones accumulate near the center.
The results get scooped up continually. Rows of centrifuges
repeat the process to slowly raise the rare isotope's concentration.
It seems easy. But the centrifuges spin at about the speed of sound,
must work day and night for months or years on end and can
easily lose their balance, tearing themselves apart.
"Our machines broke down frequently" in the program's early
days, Gholamreza Aghazadeh, chief of the Iranian Atomic Energy
Organization, said in a 2006 interview on state television.
He said a study had traced the failures to centrifuge assembly
when technicians with bare hands inadvertently left behind clusters
of microbes.
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